Ravenscar-Java is a subset of Java (augmented by the Real-Time Specification for Java) targeted at high-integrity real-time systems. It has recently been extended to support multiple applications of mixed criticality on the same Java platform. A two level scheduling model is used to achieve temporal isolation between applications. This paper presents the general schedulability analysis for the approach, describes how the approach can be implemented using standard real-time POSIX facilities, illustrates how the analysis can be modified to take into account the implementation, and uses the prototype implementation to evaluate the accuracy of the analysis models.